Rhipsalis does look a good bet, there are several species in the area around Rio de Janeiro. R. pachyptera is one of them, I have checked out all the species and there is more than one which could fit this plant, Rhipsalis crispata is also present.
https://sites.google.com/site/...
Rhipsalis crispata looks to have too many lobes ..
http://reflora.jbrj.gov.br/jab...
